Mi Can, Luo Chang, Wang Zigang, Zhang Yongguang, Yang Shenbo, Wang Zhifeng
School of Materials Science and Engineering, Hebei University of Technology, Tianjin 300401, China.
Key Laboratory for New Type of Functional Materials in Hebei Province, Hebei University of Technology, Tianjin 300401, China.
Materials (Basel). 2023 Oct 31;16(21):6980. doi: 10.3390/ma16216980.
Due to its extremely high theoretical mass specific capacity, silicon is considered to be the most promising anode material for lithium-ion batteries (LIBs). However, serious volume expansion and poor conductivity limit its commercial application. Herein, dealloying treatments of spray dryed Al-Si-Cu-Ni particles are performed to obtain a Cu/Ni co-doped Si-based anode material with a porous nanowire network structure. The porous structure enables the material to adapt to the volume changes in the cycle process. Moreover, the density functional theory (DFT) calculations show that the co-doping of Cu and Ni can improve the capture ability towards Li, which can accelerate the electron migration rate of the material. Based on the above advantages, the as-prepared material presents excellent electrochemical performance, delivering a reversible capacity of 1092.4 mAh g after 100 cycles at 100 mA g. Even after 500 cycles, it still retains 818.7 mAh g at 500 mA g. This study is expected to provide ideas for the preparation and optimization of Si-based anodes with good electrochemical performance.
由于其极高的理论质量比容量，硅被认为是锂离子电池（LIBs）最有前景的负极材料。然而，严重的体积膨胀和较差的导电性限制了其商业应用。在此，对喷雾干燥的Al-Si-Cu-Ni颗粒进行脱合金处理，以获得具有多孔纳米线网络结构的Cu/Ni共掺杂硅基负极材料。多孔结构使材料能够适应循环过程中的体积变化。此外，密度泛函理论（DFT）计算表明，Cu和Ni的共掺杂可以提高对Li的捕获能力，从而加速材料的电子迁移速率。基于上述优点，所制备的材料呈现出优异的电化学性能，在100 mA g下循环100次后可逆容量为1092.4 mAh g。即使在500次循环后，在500 mA g下仍保留818.7 mAh g。本研究有望为制备和优化具有良好电化学性能的硅基负极提供思路。
